Three federal prisoners have been indicted on charges of assaulting U.S. marshals and other guards who escorted them to and from a federal racketeering trial in Baltimore.

John Harrison, 28, Taurus Tillman, 29, and Brandon Wilson, 24, were convicted in October of racketeering and drug crimes. Prosecutors said the three men and five co-defendants ran a murderous West Baltimore drug crew known as “Trained To Go.” All eight were convicted during a 24-day trial in U.S. District Court in Baltimore.

As their trial proceeded, security measures increased. In a break from routine, the marshals began leaving Harrison handcuffed in the courtroom. Officials had declined to discuss reasons for the strict measures.

In the indictments unsealed Thursday, prosecutors allege the three men threw punches and elbows at the guards behind closed doors.

Harrison punched and elbowed one marshal while being escorted from the courtroom during a break in trial, prosecutors wrote in the indictment. Tillman tried to help Harrison, they wrote. He allegedly began “vigorously punching” another marshal in the head.

In a separate incident, Wilson allegedly beat two jailhouse guards. Federal prosecutors say he threw punches at the two corrections officers who were taking him to court.

Harrison, Tillman and Wilson were indicted on charges of assaulting the marshals. Each faces eight years in prison if convicted. Online court records did not list their defense attorneys.

“The brave men and women of the U.S. Marshals Service are critical to our justice system and we will not tolerate assaults on them,” U.S. Attorney for Maryland Robert Hur said in a statement.

During the five-week trial, prosecutors and witnesses described how Barronette and Sivells climbed from street-level drug dealers to lead a powerful crew that sold heroin and served as guns for hire. Jurors saw the defendants’ Instagram pages, where the men posted photos of themselves with stacks of cash and guns. “Run the city,” one wrote, “#snipergang.”

The jury found members of the gang murdered nine people, threatened witnesses and dealt large quantities of heroin — at least 1,000 grams — around the Sandtown-Winchester neighborhood.

The eight men all face life in federal prison. They have not been scheduled for sentencing.